Switch-to-talk functionality for multivoice two-way radios

ABSTRACT

A multivoice radio system allows users to speak and listen, at the same time, to others using multivoice radios without using a base station. Several embodiments of the present invention are directed toward combining a multivoice radio with push-to-talk (PTT), long-range radio. Other embodiments combine two or more multivoice systems and/or use an extender to increase a distance that multivoice radios can communicate with each other. Combining multivoice systems, in some embodiments, creates a voice and/or data mesh network. Switch-to-talk (STT) functionality can be added to systems to increase a number of users and promote radio discipline. Additionally, a combined in-ear microphone and speaker is disclosed. Further embodiments are directed to combining duplex radios, such as mobile phones, to multivoice systems, and/or PTT systems.

This application is a continuation of U.S. application Ser. No.13/863,282, filed Apr. 15, 2013, which claims the benefit of and is anon-provisional of U.S. Applications No. 61/623,662 filed on Apr. 13,2012, No. 61/681,399 filed on Aug. 9, 2012, and No. 61/751,727 filed onJan. 11, 2013, each of which is hereby expressly incorporated byreference in its entirety for all purposes.

BACKGROUND

This disclosure relates in general to radio communication, and morespecifically, without limitation, to two-way portable radiocommunication and time-division multiplexed communication. Two-wayradios, generally referred in this application as simply radios, enablewireless communication between two or more people. To operate, manyradios require either a push-to-talk (PTT) button or a voice operatedswitch (VOX). For example, walkie-talkies today require either a PTTbutton or VOX. One disadvantage of both PTT and VOX is that both PTT andVOX communications are half-duplex. In half-duplex communication, aradio can either transmit or receive at a given time, not both. In thisapplication, the term PTT radio generally refers to radios usinghalf-duplex communication where a user can either speak or listen at agiven time, not both.

Full-duplex communication, commonly referred to as duplex communication,permits a radio to simultaneously transmit and receive at the same time,enabling a user of a duplex radio to both speak and listen at the sametime. One way a radio can operate in a duplex mode, without needing aPTT button or VOX, is by using a base station. An example of wirelessradios connected by a base station, and thus enabling full-duplexcommunication, is two users talking to each other using cell phones.Another example of wireless radios connected by a base station is a hometelephone system with wireless telephones that can be placed in aconferencing mode.

SUMMARY

Radios can operate in duplex communication without a base-station usingtime division multiplexing such as a time-division multiple access(TDMA) protocol. An example of radios communicating using a TDMAprotocol system to create a wireless-conferencing system that does notuse a base station is disclosed in U.S. patent application Ser. No.10/194,115, filed on Jul. 11, 2002. A conferencing system similar tothat disclosed in application '115 is also referred to in thisapplication as a multivoice system. A radio that operates using awireless-conferencing system similar to the '115 application is referredto in this application as a multivoice radio. A multivoice system allowsusers to speak and listen, at the same time, to others using multivoiceradios. Several embodiments of the present invention are directed towardcombining a multivoice radio with a PTT radio. Other embodiments combinetwo or more multivoice systems and/or use an extender to increase adistance that multivoice radios can communicate with each other.Combining multivoice systems, in some embodiments, creates a voiceand/or data mesh network. Further embodiments are directed to combiningduplex radios, such as mobile phones, to multivoice systems, and/or PTTsystems. Different embodiments of radio transmission can include directsequence spread spectrum communication, frequency hopping spreadspectrum communication, and/or single channel communication.

Embodiments of systems and methods for implementing a switch-to-talkfunctionality for radios in a TDMA system are disclosed. A radio in aTDMA system is configured to operate in two modes, a “listen” mode and a“transmit” mode. When the radio operates in the listen mode, the radioreceives wireless communication from other radios, but the radio is notassigned a transmission slot for transmitting audio communication. Whenthe radio operates in the transmit mode, the radio is assigned to atransmission slot to transmit audio communication. Though examples aredirected to TDMA, similar approaches could be used in other areas, suchas in other multiple access protocols.

Further areas of applicability of the present disclosure will becomeapparent from the detailed description provided hereinafter. It shouldbe understood that the detailed description and specific examples, whileindicating various embodiments, are intended for purposes ofillustration only and are not intended to necessarily limit the scope ofthe disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure is described in conjunction with the appendedfigures:

FIG. 1 depicts a block diagram of an embodiment of a signal compounderconnected to a first transceiver, a second transceiver, and a headsethaving a microphone and a speaker;

FIG. 2A depicts a block diagram of an embodiment of a combinedshort-range and long-range radio system using a signal compounder housedin a short-range and long-range (SLR) radio;

FIGS. 2B and 2C depict block diagrams of an embodiment of a combinedshort-range and long-range radio system using a signal compounder housedin a multivoice radio and connected to a long-range radio;

FIGS. 2D and 2E depict block diagrams of an embodiment of a multivoicesystem combined with a long-range radio without using a signalcompounder;

FIG. 2F depicts a block diagram of an embodiment of a combinedshort-range and long-range radio system with a signal compounderconnected to a multivoice radio as the first transceiver and the signalcompounder connected to a long-range radio as the second transceiver;

FIGS. 3A, 3B, and 3C depict block diagrams of embodiments of differentcommunication modes of a combined short-range and long-range radiosystem;

FIG. 4 depicts a block diagram of an embodiment of the signal compoundershowing different modes for privacy selection of the microphone;

FIGS. 5A and 5B depict schematic diagrams of embodiments of the signalcompounder for combining two radio systems;

FIGS. 6A and 6B depict schematic diagrams of embodiments of the signalcompounder showing switches for different mode selections;

FIG. 7 depicts a schematic diagram of an embodiment for a combinedin-ear microphone and speaker;

FIG. 8 depicts a block diagram of an embodiment of a first multivoicesystem combined with a second multivoice system using a dualtransceiver;

FIG. 9 depicts a block diagram of an embodiment of a first multivoicesystem combined with a second multivoice system using an external signalcompounder;

FIG. 10A depicts a block diagram of an embodiment of a signal compoundercombining two multivoice systems and a duplex radio;

FIG. 10B depicts a schematic diagram of an embodiment of a signalcompounder combining two multivoice systems and a duplex radio;

FIG. 11 depicts a block diagram of an embodiment of a signal compoundercombining two duplex radio systems that use base stations;

FIG. 12 depicts a block diagram of an embodiment using two signalcompounders to combine three multivoice systems;

FIG. 13 depicts a block diagram of an embodiment of a signal compoundercombining two duplex systems that use base stations with a long-rangeradio;

FIG. 14 depicts a block diagram of two signal compounder combining threemultivoice systems with use of duplex radios;

FIG. 15 depicts a block diagram of group range extenders used toincrease a range of a multivoice system;

FIGS. 16A and 16B illustrate flowcharts of embodiments of processessynchronization of group range extenders;

FIG. 17 depicts a block diagram of an example embodiment of a meshnetwork; and

FIG. 18 illustrates a flowchart of an embodiment of a process forconfiguring a radio to switch between a transmit mode and a listen-onlymode.

In the appended figures, similar components and/or features may have thesame reference label. Further, various components of the same type maybe distinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If only the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label.

DETAILED DESCRIPTION

The subject matter of embodiments of the present invention is describedhere with specificity to meet statutory requirements, but thisdescription is not necessarily intended to limit the scope of theclaims. The claimed subject matter may be embodied in other ways, mayinclude different elements or steps, and may be used in conjunction withother existing or future technologies. This description should not beinterpreted as implying any particular order or arrangement among orbetween various steps or elements except when the order of individualsteps or arrangement of elements is explicitly described.

Several embodiments of the present invention are directed towardcombining a multivoice radio with a PTT radio. Other embodiments combinetwo or more multivoice systems and/or use an extender to increase adistance that multivoice radios can communicate with each other.Combining multivoice systems, in some embodiments, creates a voiceand/or data mesh network. Further embodiments are directed to combiningduplex radios, such as mobile phones, with multivoice systems, and/orPTT systems. Other embodiments are directed to a switch-to-talk featurefor a radio. Still other embodiments are for a combined in-earmicrophone and speaker. Different embodiments of radio transmission caninclude direct sequence spread spectrum communication, frequency hoppingspread spectrum communication, and/or single channel communication.

With reference to FIG. 1, a block diagram is shown of an embodiment of asignal compounder 104 connected to a first transceiver 108, a secondtransceiver 110, and a headset 120 having a microphone 112 and a speaker116. The first transceiver 108 operates in a first frequency band. Afrequency band is a range of one or more frequencies in anelectromagnetic spectrum. The first transceiver communicates with afirst set of radios operating in the first frequency band. The first setof radios includes one or more radios. In different embodiments thefirst set of radios includes PTT radios, multivoice radios, and/orduplex radios. In different embodiments the first set of radios may alsocontain or be connected to a Global Positioning Satellite (GPS)receiver.

The second transceiver 110 operates in a second frequency band. In someembodiments, there is total overlap of frequencies in the firstfrequency band and the second frequency band. For example, the firstfrequency band could be the same as the second frequency band or thesecond frequency band could be a subset of frequencies of the firstfrequency band. In other embodiments there is partial overlap offrequencies in the first frequency band and the second frequency band.In still further embodiments, there is no overlap of frequencies in thefirst frequency band and the second frequency band. The secondtransceiver 110 communicates with a second set of radios. The second setof radios includes one or more radios. The second set of radios cancomprise PTT radios, multivoice radios, and/or duplex radios.

In the embodiment shown, the microphone 112 and speaker 116 are parts ofa headset 120. For example, the speaker 116 could be mono or stereoheadphones that cover ears of a user with the microphone 112 attached toa boom. In other embodiments, the speaker 116 and microphone 112 arecombined in a single in-ear piece. In still further embodiments, thespeaker 116 and microphone 112 are built into a same housing as atransceiver. Various combinations or permutations of where the speaker116 and microphone 112 are located can also be selected, such as using aspeaker 116 in a headset 120 but using a built-in microphone 112.

The signal compounder 104 can combine various signals by multiplexingand/or separate various signals by demultiplexing. The signal compounder104 receives a first signal from the first transceiver 108 and a secondsignal from the second transceiver 110. The signal compounder 104 canreceive the first signal from the first transceiver 108 and the secondsignal from the second transceiver 110 by a wire (e.g., physicalconnector) and/or wirelessly (e.g., Bluetooth). The signal compounder104 combines the first signal with the second signal to make a firstcombined signal. The signal compounder 104 transmits the combined signalto the speaker 116 either by a wire or wirelessly. The speaker 116transduces the first combined signal to audio for the user.

The signal compounder 104 also receives a third signal from a microphone112. The signal compounder 104 can receive the third signal through awire or wirelessly. The microphone 112 transduces audio, such as speechof the user, into the third signal. The signal compounder 104 combinesthe third signal from the microphone 112 with the second signal from thesecond transceiver 110 to create a second combined signal. The signalcompounder 104 transmits the second combined signal to the firsttransceiver 108 for transmission to the first set of radios. The signalcompounder 104 combines the third signal from the microphone 112 withthe first signal from the first transceiver 108 to create a thirdcombined signal. The signal compounder 104 transmits the third combinedsignal to the second transceiver 110 for transmission to the second setof radios. The signal compounder 104 can also include various combiningalgorithms, filters, echo cancellation, etc. The signal compounder 104,in certain embodiments, allows the user to switch between various modesand privacy settings, such as allowing the first transceiver 108 toreceive communication from the second transceiver 110, but not lettingthe second transceiver receive communications from the first transceiver108.

Referring next to FIG. 2A, a block diagram of an embodiment of acombined short-range and long-range radio system using a signalcompounder 104 housed in a short-range and long-range (SLR) radio 212 isshown. The SLR radio 212 is a dual-transceiver radio housing the firsttransceiver 108 and the second transceiver 110. The SLR radio alsoincludes a microphone 112 and a speaker 116, either connected as aheadset 120 or integrated into the housing of the SLR radio 212. In thisand other embodiments, each radio has a microphone 112 and a speaker116, either built in and/or connected (either wired or wirelessly). TheSLR radio 212 is shown communicating with a plurality of other radios.The SLR radio 212 communicates, via the first transceiver 108, with botha first multivoice radio 204-1 and a second multivoice radio 204-2. Thefirst multivoice radio 204-1 and the second multivoice radio 204-2 areshort-range radios operating in the first frequency band. The SLR radio212 also communicates, via the second transceiver 110, with a long-rangeradio 220. The long-range radio 220 is a PTT radio and operates in thesecond frequency band. In this embodiment, there is no overlap offrequencies in the first frequency band and the second frequency band.

The first multivoice radio 204-1 transmits a first short-range signal208-1 to both the second multivoice radio 204-2 and the SLR radio 212.The SLR radio 212 and the second the second multivoice radio 204-2receive the first short-range signal 208-1. The second multivoice radio204-2 transmits a second short-range signal 208-2 to both the firstshort-range radio 204-1 and the SLR radio 212. The short range signals208 are transmitted in the first frequency band. The long-range radio220 transmits a first long-range signal 216-1 to the SLR radio 212.

The signal compounder 104, in the SLR radio 212, combines the firstshort-range signal 208-1, the second short-range signal 208-2, and thefirst long-range signal 216-1 to create a first combined signal. The SLRradio 212 then transmits the first combined signal to the speaker 116 ofthe SLR radio 212. Thus a user of the SLR radio 212 can hearcommunication from the first multivoice radio 204-1, the secondmultivoice radio 204-2, and the long-range radio 220.

The signal compounder 104 combines the signal from the microphone 112 ofthe SLR radio 212 with the second long-range signal 216-1 to create asecond combined signal. Signals can be combined using techniques knownin the art. For example, signals can be multiplexed and/or summed. TheSLR radio 212 transmits a third short-range signal 208-3 to both thefirst multivoice radio 204-1 and the second multivoice radio 204-2,where the third short-range signal 208-3 carries the second combinedsignal. Thus users of the first multivoice radio 204-1 and the secondmultivoice radio 204-2 can hear communication from the SLR radio 212 andthe long-range radio 220.

The signal compounder 104 combines the signal from the microphone 112with the first short-range signal 208-1 and the second short-rangesignal 208-2 to create a third combined signal. The SLR radio 212transmits a second long-range signal 216-2 to the long-range radio 220,the second long-range signal 216-2 carrying the third combined signal.Thus a user of the long-range radio 220 can hear communication from theSLR radio 212, the first short-range radio 204-1, and the secondshort-range radio 204-2.

To aid in understanding embodiments of the invention, in this and otherfigures, a letter is assigned to a radio and/or headset and written nextto a signal to show a composition of that signal. As shown in thefigure, the SLR radio 212 is labeled with an A, the first multivoiceradio 204-1 is labeled with a B, and the second multivoice radio 204-2is labeled with a C. Under the second long-range signal 216-2 is written“A+B+C” to signify that the second long-range signal 216-2 carriescommunication from the SLR radio 212, the first multivoice radio 204-1,and the second multivoice radio 204-2.

Referring next to FIGS. 2B and 2C, block diagrams of an embodiment of acombined short-range and long-range radio system using a modifiedmultivoice (MMV) radio 206 connected to a first long-range radio 220-1are shown. In FIG. 2B, a multivoice radio 204 is modified by adding asignal compounder 104 in the same housing as the multivoice radio 204,creating an MMV radio 206. FIG. 2B is similar to FIG. 2A, except thefirst multivoice radio 204-1 is replaced with a first MMV radio 206-1;the second multivoice radio 204-2 is replaced with a second MMV radio206-2; and the SLR radio 212 is replaced with a combination of a thirdMMV radio 206-3 and the first long-range radio 220-1. Thus instead of asingle radio, the SLR radio 212, housing the signal compounder 104, thefirst transceiver 108, and the second transceiver 110; the third MMVradio 206-3 houses the first transceiver 108, and the signal compounder104 and the first long-range radio acts as the second transceiver 110.The third MMV radio 206-3 is connected to the first long-range radio220-1 by a wired connection 228 comprising one or more wires. The wiredconnection 228 may contain voice and/or data. The first long-range radio220-1 transmits and receives radio signals from a second long-rangeradio 220-2. Although the third MMV radio 206-3 is shown connected tothe first long-range radio 220-1 by a wired connection 228 a wirelessconnection may also be used.

The signal compounder 104 in the third MMV radio 206-3 combinesdifferent signals in a manner similar to the signal compounder 104 inthe SLR radio 212 in FIG. 2A. For example, a user of the first MMV radio206-1 can hear users of the third MMV radio 206-3 and the secondlong-range radio 220-2. The user of the second long-range radio 220-2can hear users of the first MMV radio 206-1 and the second MMV radio206-2 through the third MMV radio 206-3 and the first long-range radio220-1. In this figure, the first MMV radio 206-1 and the second MMV206-2 are shown. The first MMV radio 206-1 could be replaced with thefirst multivoice radio 204-1 and/or the second MMV radio 206-2 could bereplaced with the second multivoice radio 204-1 and still have similarfunctionality.

FIG. 2C shows more details in the connection between the third MMV radio206-3 and the first long-range radio 220-1 of FIG. 2B according to someembodiments of the invention. The third MMV radio 206-3 has both aheadset port 232-1 and an auxiliary port 236. The first long-range radio220-1 has a headset port 232-2. A headset port 232 allows a connectionto an external microphone 112 and/or speaker 116, such as by allowing aheadset 120 to be plugged into the headset port 232. Different radioshave different types of headset ports 232. For example, a headset port232 could receive a cylindrical audio connector, such as a standard 6.35mm, 3.5 mm, or 2.5 mm diameter TS, TRS, and/or TRRS connector. Or theheadset port 232 could have a proprietary or standard multi-pinreceptacle.

The wired connection 228 connects the auxiliary port 236 of the thirdMMV radio 206-3 to the headset port 232-2 of the first long-range radio220-1. In some embodiments, plugging a connector into a headset port 232can disable a built-in microphone and/or speaker. Connecting the wiredconnection 228 to the auxiliary port 236 of the third MMV radio 206-3allows a user to still use the microphone 112 and the speaker 116 of thethird MMV radio 206-3.

Referring next to FIGS. 2D and 2E, block diagrams of an embodiment of amultivoice system combined with a long-range radio without using asignal compounder 104 are shown. FIG. 2D is similar to FIG. 2B exceptthe first MMV radio 206-1, is replaced with the first multivoice radio204-1, the second MMV radio 206-2 is replaced with the second multivoiceradio 204-2 and the third MMV radio is replaced with a third multivoiceradio 204-3. The third multivoice radio 204-3 is connected by the wiredconnection 228 to the first long-range radio 220-1.

FIG. 2E shows a more detailed connection between the third multivoiceradio 204-3 and the first long-range radio 220-1 of FIG. 2D according tosome embodiments of the invention. FIG. 2E shows the third multivoiceradio 204-3 with a headset port 232-1. The second long-range radio 220-1with a headset port 232-2 is also shown. The wired connection 228connects the headset port 232-1 of the third multivoice radio 204-1 tothe headset port 232-2 of the first long-range radio 220-1. In thisconfiguration, a speaker output of the second long-range radio 220-1becomes a microphone input to the third multivoice radio 204-3. And aspeaker output of the third multivoice radio 204-3 becomes a microphoneinput to the first long-range radio 220-1. The third multivoice radio204-3 treats signals received from the first long-range radio 220-1 asan input signal and multiplexes the signals received from the long-rangeradio 220-1 for transmission to the first multivoice radio 204-1 and thesecond multivoice radio 204-2.

Referring next to FIG. 2F, a block diagram of an embodiment of acombined short-range and long-range radio system with the signalcompounder 104 not embedded in a radio is shown. FIG. 2F is similar toFIG. 2A, except the SLR radio 212 is replaced with a combination of thesignal compounder 104, the third multivoice radio 204-3, the firstlong-range radio 220-1, and a headset 120. The signal compounder 104 isin its own housing (i.e., not embedded in another radio). The signalcompounder 104 is connected to the third multivoice radio 204-3 througha first wired connection 228-1. The signal compounder 104 is connectedto the first long-range radio 220-1 through a second wired connection228-2. The signal compounder 104 is connected to the headset 120. Thethird multivoice radio 204-3 acts as the first transceiver 108 and thefirst long-range radio 220-1 acts as the second transceiver. The firstlong-range radio 220-1 transmits and receives signals from a secondlong-range radio 220-2. The third multivoice radio 204-3 transmits andreceives signals from the first multivoice radio 204-1 and the secondmultivoice radio 204-2. More multivoice radios 204 and/or long rangeradios 220 could be added. For example, there could be eight multivoiceradios 204 communicating with each other and the third multivoice radio204-3.

In one embodiment, the wired connection 228-1 between the signalcompounder 104 and the third multivoice radio 204-3 includes six wires.Two wires are used to differentially drive a speaker. Two wires are usedto differentially drive a microphone. One wire is used to transmit powerfrom the third multivoice radio 204-3 to the signal compounder 104. Andone wire is used as ground. Various other embodiments can includedifferent numbers of wires and other wire configurations. For example, afour wire connector could include one speaker wire, one microphone wire,ground, and a wire for power. Or a connector could have two, three, orfour wires, such as for connecting to a mobile telephone for connectingto audio port.

The signal compounder 104 in FIG. 2F functions similarly to the signalcompounder 104 housed in the SLR radio 212 in FIG. 2A. The signalcompounder 104 combines signals from the headset 120, the thirdmultivoice radio 204-3 and the first long-range radio 220-1. Forexample, the first multivoice radio 204-1 receives communications fromthe headset 120 and the second long-range radio 220-2. The secondlong-range radio 220-2 receives communications from the headset 120 andthe first multivoice radio 204-1. By using the signal compounder 104 ina separate housing, inputs and outputs can be summed and/or excludedsimilarly to the embodiments shown for the SLR radio 212.

In FIGS. 3A, 3B, and 3C, embodiments of different modes, or privacyconfigurations, are shown. FIGS. 3A, 3B, and 3C are similar to the SLRsystem previously described in FIG. 2A, but with changes as describedbelow. In FIG. 3A, the SLR radio 212 transmits the third short-rangesignal 208-3, which contains communications from the SLR radio 212(i.e., from a user through the microphone 112) and communications fromthe long-range radio 220. But instead of transmitting the secondlong-range signal 216-2, the SLR radio 212 transmits a third long-rangesignal 216-3 that includes communication from SLR radio 212, but notcommunications from the multivoice radios 204. Thus users of the firstmultivoice radio 204-1 and the second multivoice radio 204-2 can hearcommunication from the SLR radio 212 and the long-range radio 220. But auser of the long-range radio 220 cannot hear communication from thefirst multivoice radio 204-1 or the second multivoice radio 204-2. Auser of the SLR radio 212 can hear communication from the firstmultivoice radio 204-1, the second multivoice radio 204-2, and thelong-range radio 220.

In FIG. 3B, the SLR radio 212 transmits the second long-range signal216-2, which contains communications from the SLR radio 212, the firstmultivoice radio 204-1, and the second multivoice radio 204-2. But theSLR radio 212 does not transmit the third short-range signal 208-3.Instead, the SLR radio 212 transmits a fourth short-range signal 208-4to the first multivoice radio 204-1 and the second multivoice radio204-2 that include communication from the SLR radio 212, but notcommunications from the long-range radio 220. Thus the user of thelong-range radio 220 can hear communication from the SLR radio 212, thefirst multivoice radio 204-1, and the second multi-voice radio 204-2.But the first multivoice radio 204-1 and the second multivoice radio204-2 do not hear communication from the long-range radio 220.

In FIG. 3C, the SLR radio 212 still transmits the third short-rangesignal 208-3, which contains communications from the SLR radio 212 andthe long-range radio 220. But instead of the second long-range signal216-2, the SLR radio 212 transmits a fourth long-range signal 216-4 thatcontains communications from the SLR radio 212 and the first multivoiceradio 204-1, but not communication from the second multivoice radio204-2 (even though the second multivoice radio 204-2 is transmitting).Thus users of the first multivoice radio 204-1 and the second multivoiceradio 204-2 can hear communication from the long-range radio 220. A userof the long-range radio 220 can hear communication from the firstmultivoice radio 204-1, but cannot hear communication from the secondmultivoice radio 204-2.

Other permutations of combined signals can be used, but are not shown.For example, a user of the SLR radio 212 could mute the microphone 112so that neither the multivoice radios 204 nor the long-range radio 220receive communication from the SLR radio 212; but the multivoice radios204 and the long-range radio 220 could still receive communication fromeach other. Additionally, in one embodiment a user of the SLR radio 212changes between modes using switches, toggles, touchscreen inputs, voicecommands, and/or buttons on the SLR radio 212.

Though embodiments in certain figures have been illustrated using an SLRradio 212, similar modes for combining and/or excluding signals can alsobe performed using the signal compounders 104 in systems as described inFIGS. 2B and 2F. For example, the signal compounder 104 in FIG. 2F thatis attached to the third multivoice radio 204-3, the first long-rangeradio 220-1, and the headset 120, can replace the SLR radio 212 in FIGS.3A, 3B, and 3C.

FIG. 4 shows a block diagram of an embodiment of a portion of the signalcompounder 104. In this embodiment, the signal compounder 104 isconnected to the first transceiver 108, the second transceiver 110, andthe microphone 112. The signal compounder 104 has four modes fortransmitting signals from the microphone 112. In a first mode 404 fortransmitting signals from the microphone 112, a signal from themicrophone is transmitted to the first transceiver 108, but not thesecond transceiver 110. In a second mode 408 for transmitting signalsfrom the microphone 112, the signal from the microphone 112 istransmitted to both the first transceiver 108 and the second transceiver110. In a third mode 412 for transmitting signals from the microphone112, the signal from the microphone 112 is transmitted to the secondtransceiver 110, but not to the first transceiver 108. In the fourthmode 416 for transmitting signals from the microphone 112, the signalfrom the microphone is not transmitted to either the first transceiver108 or the second transceiver 110 (i.e., muted).

The first mode 404, the second mode 408, the third mode 412, and thefourth mode 416 can be selected or toggled between using one or moreswitches, toggles, and/or buttons. For example, in one embodiment thefourth mode 416 is the default mode and the microphone 112 is mutedunless a user presses a transmit button. In combination with thetransmit button, a selection switch selects either the first mode 404,the second mode 408, or the third mode 412. When the selection switchindicates the second mode 408, and the transmit button is pressed, thesignal compounder 104 transmits signals from the microphone 112 to boththe first transceiver 108 and the second transceiver 110. When theselection switch indicates the first mode 404, and the transmit buttonis depressed, the signal compounder 104 transmits signals from themicrophone 112 to the first transceiver 108, but not the secondtransceiver 110. If the transmit button is not depressed, the signalcompounder operates in the fourth mode 416 and the microphone 112 ismuted. The signal compounder 104 does not need to have all four modes.For example, the signal compounder 104 could have just the first mode404, the second mode 408, and the third mode 412. The signal compounder104 could just have the first mode 404 and the second mode 408. Or thesignal compounder 104 could have just the second mode 408 and the fourthmode 416. In this way, a user with the headset 120 can communicate usingboth the first transceiver 108 and the second transceiver 110 and havethe flexibility to switch between modes.

Referring next to FIGS. 5A and 5B, schematic diagrams of embodiments ofthe signal compounder 104 for combining two radio systems are shown.FIG. 5A shows an embodiment of the signal compounder 104. The signalcompounder 104 receives a first signal from the first transceiver 108 ata first input 532. A first amplifier 508-1 amplifies the first signal.The signal compounder 104 receives a second signal at a second input540. A second amplifier 508-2 amplifies the second signal. The signalcompounder 104 receives a microphone signal from the microphone 112 at amicrophone input 560. A microphone amplifier 516 amplifies themicrophone signal. Amplifies can mean attenuates and/or buffers.

At a first junction 561-1, the signal compounder 104 combines the secondsignal with the third signal to create a first combined signal. A firstdriver 512-1 amplifies and/or attenuates the first combined signal, andthe first combined signal is transmitted to the first transceiver 108via a first output 536. At a second junction 561-2, the signalcompounder 104 combines the first signal with the microphone signal tocreate a second combined signal. A second driver 512-2 amplifies and/orattenuates the second combined signal, and the second combined signal istransmitted to the second transceiver 110 via a second output 544. At athird junction 561-3, the signal compounder 104 combines the firstsignal and the second signal to create a third combined signal. Aspeaker driver 520 amplifies and/or attenuates the third combinedsignal, and the third combined signal is transmitted to the speaker 116via a speaker output 556.

The signal compounder 104 also includes a plurality of resistors 528.Resistors 528 can optionally be removed to semi-permanently limitcertain signals. For example, removing a first resistor 528-1 configuresthe signal compounder 104 so that the second signal is not transmittedto the first transceiver 108, but the second signal is still transmittedto the speaker 116. Thus a user of the second transceiver 110 couldlisten to communication from the first transceiver, but the otherresistors 528 can be removed to limit transmission of other signals.

The signal compounder 104 also includes a power source 504. The powersource 504 powers various components such as the amplifiers 508, thedrivers 512, the microphone amplifier 516, and/or the speaker driver520. The power source 504 can be a battery or powered through aconnection to a radio. The power source 504, the amplifiers 508, thedrivers 512, the microphone amplifier 516, the speaker driver 520, andresistors are optional. The amplifiers 508, the drivers 512, themicrophone amplifier 516, and/or the speaker driver 520 help balancevolume levels between different signals.

Referring next to FIG. 5B, another embodiment of the signal compounder104 is shown. In addition to the features already described in FIG. 5A,FIG. 5B adds a PTT jumper section 524. The PTT jumper is inserted beforethe second output 544. The PTT jumper section 524 allows a user of thesignal compounder 104 to remotely activate a push-to-talk function onthe second transceiver 110. Other embodiments could place a PTT jumpersection 524 to activate a push-to-talk function on the first transceiver108 either as an alternative to, or in combination with, the PTT jumpersection 524 to activate the push-to-talk function on the secondtransceiver 110.

Different PTT radios use different techniques to activate a transmitterin long-range radio 220. One method is to disconnect and connect thefourth output 544 from the second driver 512-2 or the microphone bias557. Using the PTT jumper section 524, the second driver 512-2 outputcan be routed to a second PTT input 552. When a remote PTT button ispushed, the second PTT input 552 is connected to a first PTT input 548and the PTT jumper section 524 will route the first PTT input 548 to thesecond output 544. If a bias signal from the driver 512-2 is not used,then an external bias voltage from the microphone bias 557, which maycome from the second transceiver 110 can be connected to the second PTTinput 552 by jumpers in jumper section 524.

Another method for telling the second transceiver 110 it is time totransmit is to use a constant voltage signal to as an input to thesecond transceiver 110. When a second transceiver 110 uses thistechnique, the output of driver 512-2 is routed through the PTT jumpersection 524 and via jumpers connected to the second output 544. If anexternal bias is required by the second transceiver, then a jumper inthe PTT jumper section 524 may connect the microphone bias 557 to thesecond output 544. When applicable, the second PTT input 552 isconnected to either ground or power connection 555 by using jumpers inthe PTT jumper section 524. The power connection 555 may come from thesecond transceiver. When the remote PTT button is pushed, the second PTTinput 552 is connected to the first PTT input 548 and the PTT jumpersection 524 will route a signal to the fourth output 553, which isconnected to an input on the second transceiver 110 and notifies thesecond transceiver 110 to transmit.

Referring next to figure FIG. 6A, a schematic diagram of anotherembodiment of the signal compounder 104 is shown. FIG. 6A is similar toFIG. 5B, but FIG. 6A has a plurality of mode switches 608 and aplurality of sidetone modules 604.

The mode switches 608 can be dynamically opened and/or closed for thesignal compounder 104 to operate in different modes, such as modesdescribed in FIGS. 3A, 3B, 3C, and 4. For example, to have the signalcompounder 104 operate in the fourth mode 416 described in FIG. 4, afirst mode switch 608-1 and a second mode switch 608-2 would beconfigured in an open state. With the first mode switch 608-1 and thesecond mode switch 608-2 in an open state, a signal from the microphone112 received at the microphone input 560 is not transmitted to the firstoutput port 536 (and thus not transmitted to the first transceiver 108)or to the second output port 544(and thus not transmitted to the secondtransceiver 110). Other modes are possible through differentcombinations of opened and closed mode switches 608.

Sidetone in a headset 120 is feedback from the microphone 112 fed intothe speaker 116 so that a user hears him or herself speaking Sidetone isnot necessary, but because of the older phone systems that had sidetone,people now expect to hear sidetone and many people prefer hearingsidetone when they speak. In the above system, sidetone may cause anecho. The echo of sidetone can be eliminated or reduced by programmingradios that are connected to the signal compounder 104 to have nosidetone. When sidetone cannot be turned off, then the echo can bereduced or eliminated by using modified 2-to-4 wire converter typecircuits. The 2-to-4 wire converter senses a signal sent to each radio,inverts the signal's phase 180 degrees, and adds the inverted signalafter volume adjustment with the speaker signal coming from that sameradio in such a way as to cancel some or all of the sidetone. This isset up such that the sidetone for the headset 120 connected to thesignal compounder 104 is not canceled or that the sidetone is onlygenerated by one of the transceivers for the headset 120 that isconnected to the signal compounder 104. Sidetone modules 604 comprisethe 2-to-4 wire converter or cancellation circuit. The 2-to-4 wireconverter can be made either mechanically, using active circuits, or byusing digital signal processing (DSP).

In FIG. 6B, a schematic diagram of an embodiment of a portion of thesignal compounder 104 is shown with a cell phone on-off hook module 612.The cell phone on-off hook module 612 is connected to the second output544 of FIG. 6A. The cell phone on-off hook module 612 allows a user toremotely open a telephone connection or close (i.e., “hang up”) atelephone connection to a mobile phone connected to the signalcompounder 104. The cell phone on-off hook module 612 can be connectedwith a wire to the signal compounder 104 or connected wireless, such asusing Bluetooth technology.

In FIG. 7, a schematic diagram of an embodiment for a combined in-earmicrophone and speaker is shown. This invention covers having acombination speaker microphone in the same ear. A speaker driver 520amplifies and/or attenuates an audio signal received at a speaker input720 after going through a first filter section 704, and a resultantsignal is transmitted to the speaker 116 via a speaker output 716. Asignal from the microphone 112 is received at a microphone input 728,passes through a microphone amplifier 516, and then enters a secondfilter section 708. Because the speaker 116 and the microphone 112 areusing the same ear on a person, audio coming out of the speaker 116 maycome in on the microphone 112. To cancel or reduce the audio coming outof the speaker 116 and into the microphone 112, a signal that istransmitted to the speaker output 716 is also routed to a third filtersection 712. A signal entering the third filter section 712 is delayedand adjusted to create a 180 degree phase shift to cancel the audiocoming out of the speaker 116 and into the microphone 112. The thirdfilter section 712 may also amplify or attenuate the signal before goinginto a summing junction to be combined with the signal coming from themicrophone 112.

A signal transmitted to the speaker output 716 may be changed ordistorted from going out of the speaker 116, into the ear canal, andinto the microphone 112. The third filter section 712 can filter and/ormodify a signal entering the third filter section 712 in such a manneras to mimic the effects of the speaker 116, the ear canal, andmicrophone 112 to cancel the signal transmitted to the speaker output716. To compensate for component and/or ear canal differences, an outputof microphone amplifier 516 may be used by filter section 712 to changegain, filter, and/or phase change characteristics to cancel as much ofthe signal transmitted from the speaker output 716 as applicable from anoutput of the microphone amplifier 516.

The first filter section 704 may simply pass a signal through or mayfilter signals in such a manner as to match the characteristics of thespeaker 116. The first filter section 704 may also filter audio signalsin such manner as to help the third filter section 712 cancel feedbackfrom the speaker 116 entering the microphone 112. The first filtersection 704 may also use feedback from the microphone amplifier 516 toadjust filtering characteristics of the first filter section 704. Thefirst filter section 704 may also send data to the third filter section712 so that the third filter section 712 may change filteringcharacteristics as applicable. The second filter section 708 may modifyan output of the microphone amplifier 516 so that a signal transmittedto a microphone output 724 more resembles natural speech and/or is morerecognizable for speech recognition systems. The second filter section708 may use a signal received at the speaker input 720 to changecharacteristics of a signal received from the microphone amplifier 516to more closely match natural speech of user of the microphone 112.

In some embodiments, the speaker 115 and the microphone 112 are both inan auditory canal portion of the same ear. The microphone 112 transducescompressed air waves (i.e., sound) in the ear. In further embodiments,the microphone 112 and the speaker 115 have similar ranges. For example,the microphone 112 can transduce audio frequencies in a range that isaudible to a human ear, i.e., from 20 to 20,000 Hertz. Or the microphonecan transduce a subset of frequencies audible to a human ear; forexample from 100 to 10,000 Hertz.

FIG. 8 depicts a block diagram of an embodiment of a first multivoicesystem combined with a second multivoice system using a dual transceiver212. A first multivoice radio 204-1, a second multivoice radio 204-2 anda first SLR radio 212-1 operate in a first multivoice system and form afirst synchronized group 804-1. A synchronized group 804 is one or moremultivoice radios that are synced in time (e.g., according to TDMA) tocommunicate with each other. A second SLR radio 212-2, a thirdmultivoice radio 204-3, and a fourth multivoice radio 204-4 operate in asecond multivoice system and form a second synchronized group 804-2. Thefirst SLR radio 212-1 and the second SLR radio 212-2 are also in radiocommunication with each other. The SLR radios 212 each comprise a signalcompounder 104. The signal compounder 104 combines signals received ineach SLR radio 212 so that the first multivoice radio 204-1 and thesecond multivoice radio 204-2 in the first synchronized group 804-1 canreceive and communicate with the third multivoice radio 204-3 and thefourth multivoice radio 204-4 in the second synchronized group 804-2.Thus, by linking the first SLR radio 212-1 and the second SLR radio212-2 a larger conferencing system is formed.

FIG. 9 depicts a block diagram of an embodiment of a first multivoicesystem combined with a second multivoice system using an external signalcompounder 104. The first multivoice radio 204-1, the second multivoiceradio 204-2, and a fifth multivoice radio 204-5 form a firstsynchronized group 804-1. The third multivoice radio 204-3, the fourthmultivoice radio 204-4, and a sixth multivoice radio 204-6 form a secondsynchronized group 804-2. The signal compounder 104 is connected througha first wired connection 228-1 to the fifth multivoice radio 204-5. Thesignal compounder is connected through a second wired connection 228-2to the sixth multivoice radio 204-6. The signal compounder 104 is alsoconnected to a headset 120. The signal compounder 104 can combine andlimit signals between multivoice radios 204 in the first synchronizedgroup 804-1 and the second synchronized group 804-2 in similar ways asthe signal compounder 104 functioned in previous embodiments forcombining short-range radios with long-range radios. For example, usersof each multivoice radio 204 could hear communications from the othermultivoice radios 204, thus creating a larger conferencing system. Inanother example, a user speaking into the headset could communicate withthe first synchronized group 204-1, or the second synchronized group804-2, or both. In a further example, a user of the signal compounder104 could toggle a switch so that the first synchronized group 804-1could hear the communication in the second synchronized group 804-2, butthe second synchronized group 804-2 could not hear the communication inthe first synchronized group 804-1. The signal compounder 104 mayinclude buttons, switches, toggles, etc. that can be used by a user toswitch between any of the operational modes described herein.

FIG. 10A depicts a block diagram of an embodiment of a signal compounder104 combining two multivoice systems and a duplex radio 1004. FIG. 10Ais similar to FIG. 9, but the signal compounder 104 in FIG. 10A is alsoconnected to a first duplex radio 1004-1 through a third wired connector228-3. In one embodiment, the first duplex radio 1004-1 is a mobilephone. The first duplex radio 1004-1 is in communication with a secondduplex radio 1004-2. The first duplex radio 1004-1 receives a firstduplex signal 1008-1 from the second duplex radio 1004-2. The firstduplex radio 1004-1 transmits a second duplex signal 1008-2 to thesecond duplex radio 1004-2.

The signal compounder 104, as in FIG. 9, can receive and transmitsignals to and from the first synchronized group 804-1 and/or the secondsynchronized group 804-2. In FIG. 10A, the signal compounder 104determines which audio signals go to the first synchronized group 804-1,the second synchronized group 804-2, the headset 120, and the firstduplex radio 1004-1. Thus, for example, users of radios in the firstsynchronized group 804-1 can hear communications from users in thesecond synchronized group 804-2 as well as a user of the second duplexradio 1004-2.

In another example, a user of the second duplex radio 1004-2 can hearonly the user on the headset 120, and not users in the synchronizedgroups 804. But users in the synchronized groups 804 can hear the userof the second duplex radio 1004-2. This is what a negotiator in ahostage situation wants to occur when the negotiator has a headset 120connected to the signal compounder 104. In a hostage scenario example,users of multivoice radio systems are SWAT team members, includingsharpshooters, and the negotiator wears the headset 120 connected to thesignal compounder 104. This allows the SWAT team members to hear what asuspect is saying while the suspect is speaking on the other side of thecell phone call (i.e., on the second duplex radio 1004-2), but thesuspect can hear only what the negotiator is saying. The negotiator canhear both what the suspect is saying and what members of the SWAT teamare saying, including the sharpshooters.

In another variation of the example above about the negotiator, thenegotiator can send a robot into a building where the suspect has takena hostage. The robot can have a robot-radio system comprising aconference room microphone and speaker system connected to the firstmultivoice radio 204-1 that is part of the first synchronized group804-1. The SWAT team members have radios that are parts of the secondsynchronized group 804-2. Thus there are two different independent radioconferencing systems connected to the signal compounder 104 that isconnected to the headset 120. The negotiator, using the headset 120, canhear the suspect as part of the first synchronized group 804-1 using therobot-radio system's microphone. The negotiator can communicate with thesuspect as part of the first synchronized group 804-1 using therobot-radio system's speaker. The negotiator can also hear the SWAT teammembers in the second synchronized group 804-2. Further, the SWAT teammembers can hear what the suspect is saying. But the suspectcommunicating in the first synchronized group 804-1 hears only what thenegotiator is saying. Additionally, switch type features as shown inFIG. 6A can be added to the signal compounder 104 to isolate voice pathsuntil they are wanted.

In other embodiments, the signal compounder 104 is embedded in one ormore of the multivoice radios 204 such that combinations can becontrolled digitally. In still another embodiment, the functionality ofa multivoice radio 204 can be embedded in a cell phone or full-duplexradio. The signal compounder 104 may also be embedded in a cell phone,full duplex radio, or a multivoice radio 204.

The signal compounder 104 can combine two or more different radiosystems, or have combined modes as described herein. The signalcompounder 104 can also include various combining algorithms, filters,echo cancellation, etc. The signal compounder 104 may also multiplexsignals from the various transceivers and/or the microphone 112 as wellas demultiplex signals from the transceivers and send them to thespeaker 116. The signal compounder 104 can also be used to implementwireless conference techniques and combine two different wirelessconferencing systems so that more people can be on a larger conferencingsystem. The signal compounder 104 may also combine signals from thefirst transceiver 108 and/or the second transceiver 110 along withsignals from the speaker 116 and microphone 112. The signal compounder104 may include buttons, switches, toggles, etc. that can be used by auser to switch between different operational modes described herein. Theduplex combiner may use analog or digital techniques to combine signals.

FIG. 10B depicts a schematic diagram of an embodiment of a signalcompounder 104 combining three radio systems. FIG. 10B is similar toFIG. 6A, but FIG. 10B has the addition of connecting to a thirdtransceiver. In FIG. 10A, the third transceiver is the first duplexradio 1004-1. In FIG. 10B, the signal compounder 104 receives a thirdsignal from the third transceiver at a third input 1004. A thirdamplifier 508-3 amplifies the third signal. The signal compounder 104transmits a signal to the third transceiver via a third output 1008. Thesignal compounder 104 has a plurality of switches 608 used to controlthe combination of signals.

Inputs and outputs can be combined into ports for connecting to atransceiver. For example, the signal compounder 104 connects to thefirst transceiver 108 using a first port, the first port being used toconnect the first transceiver 108 to the first input 532 and the firstoutput 536. Likewise, a second port is used to connect the secondtransceiver 110 to the second input 540 and the second output 544. If aPTT jumper section 524 is used, as shown in this embodiment, the secondport can also be used to connect the second transceiver 110 to theoptional bias 557, the power connection 555, and/or the fourth output553. A third port is used to connect the third transceiver to the thirdinput 1004 and the third output 1008. A fourth port is used to connectthe headset 120 to the microphone input 560 and speaker output 556. Insome embodiments, the first port, the second port, the third port, andthe fourth port are all separate ports.

FIG. 11 depicts a block diagram of an embodiment of a signal compounder104 combining two duplex radio systems that use base stations. A firstduplex radio 1108-1, a second duplex radio 1108-2, and a third duplexradio 1108-3 communicate with each other via a first base station 1112-1and form a first duplex system. A fourth duplex radio 1108-4, a fifthduplex radio 1108-5, and a sixth duplex radio 1108-6 communicate witheach other via a second base station 1112-2 and form a second duplexsystem. The duplex radios 1108 and the base stations 112 transmitsignals for communication to and from the bases station 1112 referred toas base station signals 1104. A signal compounder 104 communicates withthe third duplex radio 1108-3 through a first wired connection 228-1.the signal compounder 104 communicates with the fourth duplex radio1108-4 through a second wired connection 228-2. The first wiredconnection 228-1 can connect to a headset port of the third duplex radio1108-3 and/or an auxiliary port of the third duplex radio 1108-3. Thesecond wired connection 228-2 can connect to a headset port of thefourth duplex radio 1108-4 and/or an auxiliary port of the fourth duplexradio 1108-4. The signal compounder 104 is also connected to a headset120.

The signal compounder 104 combines signals from the headset 120, thefirst duplex system, and the second duplex system in similar ways as hasbeen disclosed in previous figures and embodiments. For example,communication from a user of the first duplex radio 1108-1 istransmitted from the first duplex radio 1108-1 to the first base station1112-1; from the first base station 1112-1 to the third duplex radio1108-3; from the third duplex radio 1108-3 to the signal compounder 104via the first wired connector 228-1; from the signal compounder 104 tothe fourth duplex radio 1108-4 via the second wired connector 228-2;from the fourth duplex radio 1108-4 to the second base station 1112-2;and from the second base station 1112-2 to the fifth duplex radio 1108-5and the sixth duplex radio 1108-6. Thus users in the second duplexsystem can hear communication from users in the first duplex system.

FIG. 12 depicts a block diagram of an embodiment using two signalcompounders 104 to combine three multivoice systems. A radio in a firstsynchronized group 804-1 is connected via a first wired connection 228-1to a first signal compounder 104-1. The first signal compounder 104-1 isconnected to a first radio in a second synchronized group 804-2 via asecond wired connection 228-2. The first signal compounder 104-1 isconnected to a first headset 120-1. Thus the first synchronized group804-1, the second synchronized group 804-2, and the first headset 120-1can communicate similarly as described in FIG. 9.

A second signal compounder 104-2 connects to a second radio in thesecond synchronized group 804-2 via a third wired connector 228-3. Thesecond compounder 104-2 connects to a radio in a third synchronizedgroup 804-3 via a fourth wired connector 228-2. The second signalcompounder 104-2 is connected to a second headset 120-2. In thisembodiment, users in the first synchronized group 804-1 can communicate,via the signal compounders 104 and the second synchronized group 804-2,with users in the third synchronized group 804-3. Connecting multiplesynchronized groups 804 not only increases a number of users that cancommunicate with each other, but can also extend a range that users ofthe synchronized groups 804 can communicate with each other. Forexample, if a radio in the first synchronized group 804-1 is out ofrange of the third synchronized group 804-3, but the second synchronizedgroup 804-2 is within range of both the first synchronized group 804-1and the second synchronized group 804-2, then the first signalcompounder 104-1 can combine the first synchronized group 804-1 and thesecond synchronized group 804-2. The second signal compounder 104-2 cancombine the second synchronized group 804-2 and the third synchronizedgroup 804-3. This may result in users of radios in the firstsynchronized group 804-1 being able to communicate with users of radiosin the third synchronized group 804-3, even though the users of radiosin the first synchronized group 804-1 are out of range of users ofradios in the third synchronized group 804-3. Adding more synchronizedgroups 804 and signal compounders 104 can increase a number of usersbeing able to communicate with each other in a conference-like manner.

When a signal compounder 104 is connected to the first transceiver 108and the second transceiver 110, there is a possibility that the firsttransceiver 108 and the second transceiver 110 will interfere with eachother. One solution is to use filter designs to reduce the interference.Another solution is to have the first transceiver 108 and the secondtransceiver 110 transmit at the same time.

FIG. 13 depicts a block diagram of an embodiment of signal compounder104 combing two duplex systems using bases stations with a long-rangeradio 220. A first duplex radio 1108-1, a second duplex radio 1108-2,and a third duplex radio 1108-3 communicate with each other via a firstbase station 1112-1 and form a first duplex system. A fourth duplexradio 1108-4, a fifth duplex radio 1108-5, and a sixth duplex radio1108-6 communicate with each other via a second base station 1112-2 andform a second duplex system. The duplex radios 1108 and the basestations 112 transmit signals for communication to and from the basesstation 1112 referred to as base station signals 1104. A signalcompounder 104 communicates with the third duplex radio 1108-3 through afirst wired connection 228-1. the signal compounder 104 communicateswith the fourth duplex radio 1108-4 through a second wired connection228-2. The first wired connection 228-1 can connect to a headset port ofthe third duplex radio 1108-3 and/or an auxiliary port of the thirdduplex radio 1108-3. The second wired connection 228-2 can connect to aheadset port of the fourth duplex radio 1108-4 and/or an auxiliary portof the fourth duplex radio 1108-4. The signal compounder 104 isconnected to a headset 120. The signal compounder 104 is also connectedto a first long-range radio 120-1 via a third wired connector 228-3. Thefirst long-range radio 220-1 transmits and receives long-range signals216 to and from a second long-range radio 220-2.

The signal compounder 104 combines signals from the headset 120, thefirst duplex system, the second duplex system, and the first long-rangeradio 220-1 in similar ways as disclosed in previous figures andembodiments. For example, communication from a user of the first duplexradio 1108-1 is transmitted from the first duplex radio 1108-1 to thefirst base station 1112-1; from the first base station 1112-1 to thethird duplex radio 1108-3; from the third duplex radio 1108-3 to thesignal compounder 104 via the first wired connector 228-1; from thesignal compounder 104 to the first long-range radio 220-1 via the thirdwired connector 228-1; and from the first long-range radio 220-1 to thesecond long-range radio 220-2. Thus a user of the second long-rangeradio 220-2 can hear communication from users in the first duplexsystem, the second duplex system, and the headset 120. And users in theduplex systems can hear communication from the user of the secondlong-range radio 220-2.

Referring next to FIG. 14, a block diagram of an embodiment of twosignal compounders 104 combining three multivoice systems with use ofduplex radios is shown. A first signal compounder 104-1 is connected toa radio in a first synchronized group 804-1. The first signal compounder104-1 is connected to a first headset 120-1. The first signal compounder104-1 is connected to a first duplex radio 1401-1. The first duplexradio 1401-1 is in communication with a second duplex radio 1404-2. Theduplex radios 1404 in this embodiment are mobile phones and the firstduplex radio 1404-1 sends and receives wireless telephone signals 1408to each other either directly or through cell towers. The second duplexradio 1404-2 is connected to a second signal compounder 104-2. Thesecond signal compounder 104-2 is connected to a radio in a secondsynchronized group 804-2. The second signal compounder 104-2 isconnected to a radio in a third synchronized group 804-3. The secondsignal compounder 104-2 is connected to a second headset 120-2. Thissystem not only increases a number of user that can communicate on acombined system, using an embodiment such as this can also increase arange, or distance, between user in the combined system. For example, ifthe first synchronize group 804-1 is in Salt Lake City, Utah and thesecond synchronized group 804-2 and the third synchronized group 804-3are in New York, N.Y., then the first synchronized group 804-1 wouldnormally be out of communication range of range of the secondsynchronized group 804-2 and the third synchronized group 804-3 whenusing multivoice radios 204. But by connecting a duplex radio 1404 (suchas cell phones) to each of the signal compounders 104, users in thefirst synchronized group 804-1 can communicate in a conference-likemanner with users in the second synchronized group 804-2 and the thirdsynchronized group 804-3.

In FIG. 15, a block diagram of group range extender system 1500 used toincrease a range of a multivoice system is shown. A multivoice radiosystem uses time division multiplexing. A given time period may bedivided into a plurality of different transmission slots. For example, atransmission slot could be about three milliseconds and there could beeight transmission slots for a twenty-four millisecond time period.Radios can be categorized as either a master or slave. A master assignsitself and other radios to a transmission slot. A slave receives atransmission slot assignment from a master. A multivoice radio transmitsduring the radio's assigned transmission slot and receives during theremainder of the given time period. Table I below shows an example of anembodiment of a multivoice system with eight transmission slots andthree multivoice radios 204. Other embodiments could have differentnumber of transmission slots, such as five, six, seven, nine, ten,eleven, twelve, or thirteen. In one embodiment one or more transmissionslots are used for transmission of data other than audio. In anotherembodiment, one or more transmission slots are used for communicationbetween a master of a first multivoice radio system and a master of asecond multivoice radio system.

In Table I, a sample transmission slot assignment is shown. In thisexample, the third multivoice radio 204-3 acts as the master andassigned itself to transmission slot 1. The third multivoice radio 204-3assigned the first multivoice radio 204-1 to transmission slot 2. Thethird multivoice radio 204-3 assigned the second multivoice radio 204-2to transmission slot 3. In this example, the third multivoice radio204-3 would transmit during transmission slot 1 and the first multivoiceradio 204-1 and the second multivoice radio 204-2 would receive. Duringtransmission slot 2, the first multivoice radio 204-1 transmits and thesecond multivoice radio 204-2 and the third multivoice radio 204-3receive. During the transmission slot 3, the second multivoice radio204-2 transmits and the third multivoice radio 204-3 and the firstmultivoice radio 204-1 receive. Since transmission slots 4-8 are empty,the first multivoice radio 204-1, the second multivoice radio 204-2, andthe third multivoice radio 204-3 receive (nothing) and wait until aftertransmission slot 8 ends and transmission slot 1 begins.

TABLE I Sample Transmission Slot Assignments in a Multivoice RadioSystem Transmission Slot Radio 1 204-3 (Master) 2 204-1 (Slave) 3 204-2(Slave) 4 (empty) 5 (empty) 6 (empty) 7 (empty) 8 (empty)

In Table II, a sample transmission slot assignment for a multivoiceradio system with nine transmission slots is shown. In this example, thethird multivoice radio 204-3 acts as the master and assigned itself totransmission slot 1. The third multivoice radio 204-3 assigned the firstmultivoice radio 204-1 to transmission slot 2. The third multivoiceradio 204-3 assigned the second multivoice radio 204-2 to transmissionslot 3. This multivoice radio system also uses a ninth transmission slotfor transmitting data. In one embodiment, only a master can transmit inslot 9. In another embodiment, any radio can transmit in slot 9.

TABLE II Sample Transmission Slot Assignments in a Multivoice RadioSystem Transmission Slot Radio 1 204-3 (Master) 2 204-1 (Slave) 3 204-2(Slave) 4 (empty) 5 (empty) 6 (empty) 7 (empty) 8 (empty) 9 Data

In FIG. 9, the fifth multivoice radio 204-5 and the sixth multivoiceradio 204-6 are both masters so that the fifth multivoice radio 204-5and the sixth multivoice radio 204-6 transmit at the same time. In FIG.15 a plurality of Group Range Extenders (GREs) 1504 are shown. In oneembodiment, a GRE 1504 includes a first multivoice transceiver, a secondmultivoice transceiver, and functionality similar to the signalcompounder 104. The first multivoice transceiver is a slave and thesecond multivoice transceiver is a master. But in this embodiment, theslave of a GRE 1504 does not synchronize with the master of the same GRE1504. Instead, when a GRE 1504 is first activated, the slave of the GRE1504 searches for a master to synchronize with. After the slave of theGRE 1504 has found a master to synchronize with, then the master of theGRE 1504 activates and starts searching for slaves to synchronize.

FIG. 15 further depicts a synchronized group 804 and a first GRE 1504-1.The first GRE 1504-1 has a first transceiver that is a master and asecond transceiver that is a slave. The slave of the first GRE 1504-1synchronizes with a master in the first synchronized group 804. Themaster of the first GRE 1504-1 then activates and searches for slaves.When a slave of a second GRE 1504-2 activates, the slave of the secondGRE 1504-2 synchronizes with the master of the first GRE 1504-1. Amaster of the second GRE 1504-2 then activates and searches for slaves.A multivoice radio 204 is a slave looking for a master to synchronizewith. When the master of the second GRE 1504-2 activates, the master ofthe second GRE 1504-2 discovers the multivoice radio 204 and assigns themultivoice radio 204 a transmission slot (i.e., the multivoice radio 204and the master of the second GRE 1504-2 become synchronized). A slave ofa third GRE 1504-3 activates, searches for a master, and synchronizeswith the master of the second GRE 1504-2. A master of the third GRE1504-2 then activates and searches for slaves. A slave of a fourth GRE1504-4 activates, searches for a master, and synchronizes with themaster of the third GRE 1504-3. A master of the fourth GRE 1504-2 thenactivates and searches for slaves. A user attaches a headset 120 to thefourth GRE 1504-4. Radios in an externally synchronized group 1508 areslaves looking for a master. The radios in the externally synchronizedgroup 1508 synchronize with the master of the fourth GRE 1504-4. Thususers of radios in the externally synchronized group 1508, themultivoice radio 204, radios of the synchronized group 804, and theheadset 120 can communicate in a conference-like manner with each other.Switches on the GREs 1504 can be used to limit transmission of certainsignals similarly to the signal compounder 104. For example, a switch onthe fourth GRE 1504-4 could mute the transmission from the microphone112 of the headset 120 but allow a user of the headset 120 to monitorcommunication within the group range extender system 1500. GREs 1504synchronized with each other and the synchronized group maintain thesecurity of the system.

As an example of how GREs 1504 could be implemented is when a SWAT teamenters a building, such as a Casino, the cement walls, floors, and otherconstruction materials can inhibit radio signals from getting out of thebuilding. This can mean that the SWAT team members can lose radiocommunication to support outside the building. The support outside thebuilding, as well as the SWAT team members before the SWAT team membersenter the building are part of the synchronized group 804. By using GREs1504, a SWAT team can maintain communication with others outside thebuilding and/or inside the building. As the SWAT team members enter thebuilding, one of the SWAT team members may activate and drop, place, oreven stick to a wall a first GRE 1504-1. A slave of the first GRE 1504-1synchronizes with a master of the synchronized group 804. The master ofthe first GRE 1504-1 then activates and looks for slaves. As radios ofthe SWAT team members lose contact with the synchronized group 804, theradios of the SWAT team members start looking for another master andsynchronize with the master of the first GRE 1504-1. The radios of theSWAT team members are an externally synchronized group 1508. Thus theSWAT team members can maintain communication with the support outsidethe building by communication through the first GRE 1504-1. As the SWATteam goes deeper into the building, the SWAT team may need to activate asecond GRE 1504-2. A slave of the second GRE 1504-2 searches for amaster to synchronize with and synchronizes with the master of the firstGRE 1504-1. A master of the second GRE 1504-1 is then activated andstarts searching for slaves. As the radios of the SWAT team members losecontact with the first GRE 1504-1, the radios of the SWAT team membersstart looking for another master and synchronize with the master of thesecond GRE 1504-2. This process continues as more GREs 1504 are placed.If a first member of the SWAT team left the SWAT team to exit thebuilding, a radio of the first member of the SWAT team would losecommunication with the second GRE 1504-1 and start looking for a master.The radio of the first member of the SWAT team would find andsynchronize with the master of the first GRE 1504-1, thus enabling thefirst member of the SWAT team continued radio communication with theother members of the SWAT team and the support outside the building.

In another embodiment, a GRE 1504 may have only one transceiver insteadof two. A GRE 1504 with only one transceiver would then transmit twicein a given time period.

FIG. 16A illustrates a flowchart of an embodiment of a process 1600 forsynchronizing a GRE 1504. The process 1600 for synchronizing the GRE1504 begins in step 1604 when the GRE 1504 is activated. When the GRE1504 (i.e., turned on), a slave of the GRE 1504 is activated. After theslave of the GRE is active the slave of the GRE searches for a master tosynchronize with, step 1608. If a master is not found to synchronizewith, the slave of the GRE 1504 keeps searching for a master tosynchronize with. If the slave of the GRE 1504 finds a master, the slaveof the GRE 1504 synchronizes with the master 1616 and signals a masterof the GRE 1504 to active 1620.

The master of the GRE 1504 is activated, step 1624. If the master of theGRE 1504 is already activated, then the master of the GRE 1504 isnotified that the slave of the GRE 1504 has found a new master. Thereare various reasons the slave of the GRE 1504 might synchronize to a newmaster. For example, the GRE 1504 might be taken out of range of themaster. If the slave of the GRE 1504 is synchronized with a master, thenthe master of the GRE 1504 is notified. In step 1628, the master of theGRE 1504 searches for slaves. A determination is made whether a slave isfound, step 1632. If a slave is not found, the master of the GRE 1504searches for a slave, step 1628. If a slave is found, the master of theGRE 1504 determines a timing of the slave of the GRE 1504, step 1636.The master of the GRE 1504 could determine the timing of the slave ofthe GRE 1504 in various ways. For example, the master of the GRE 1504could receive a signal independent of a transceiver, such as throughcircuitry in the GRE 1504. In another example, the master of the GRE1504 can learn the transmission timing of the slave of the GRE 1504 on adedicated transmission slot for passing data.

After determining the transmission timing of the slave of the GRE 1504,the master of the GRE 1504 initiates a timing sequence, step 1640, andassigns the slave to a transmission slot, step 1642. The master of theGRE 1504 can also add additional slave to empty transmission slots, step1644. In an alternate embodiment, steps 1636 is omitted such that themaster of the GRE 1504 does not take into account of when the slave ofthe GRE 1504 is transmitting.

Referring next to FIG. 16B, a flowchart of another embodiment of asynchronization process 1646 for a slave of a first GRE 1504-1 is shown.In the synchronization process 1646 the slave of the first GRE 1504-1can distinguish between a non-GRE master and a master of a second GRE1504-2. The process beings in step 1604 where the slave of the first GRE1504-1 activates and starts looking for a master. In step 1648, theslave of the first GRE 1504-1 searches for a non-GRE master. Adetermination is made whether a non-GRE master is found, 1652. If anon-GRE master is found, the slave of the first GRE 1504-1 synchronizeswith the non-GRE master, step 1656, and the master of the first GRE1504-1 is signaled to activate, step 1620.

If a non-GRE master is not found in step 1652, the process flows to step1660 where the slave of the first GRE 1504-1 searches of a master of asecond GRE 1504-2. A determination is made whether the master of thesecond GRE 1504-2 is found, step 1664. If the master of the second GRE1504-2 is not found, the process returns to step 1648. If the master ofthe second GRE 1504-2 is found, then the slave of the first GRE 1504-1synchronizes with the master of the second GRE 1504-2, step 1668. Afterthe slave of the first GRE 1504-1 synchronizes with the master of thesecond GRE 1504-2, a signal is sent to the master of the first GRE1504-2 to activate, step 1620.

FIG. 17 depicts a block diagram of an example embodiment of a meshnetwork 1700. In the mesh network 1700, users on the mesh network 1700can hear one another and communicate to one another. A plurality ofGroup Mesh Devices (GMDs) 1704 are shown linking a plurality ofsynchronization groups 804. A GMD 1704 has the functionality of a signalcompounder 104 and a GRE 1504, but may also have the ability to transferdata between two multivoice radios 204. As describe previously where thesignal compounder 104 may be imbedded into a multivoice radio 204, a GMD1704 may be imbedded into a multivoice radio 204 or other kinds ofapplicable radios. The first synchronized group 804-1 may send all itsvoice and data information through a multivoice radio 204 to a first GMD1704-1 via wired connection 228-1. The first GMD 1704-1 may combine theinformation with a microphone 112, if a microphone 112 is attached tothe first GMD 1704-1, and send all the applicable voice and data throughwired connection 228-2 to a second synchronized group 804-2. Similarly,all data from the second synchronized group 804-2 is transferred throughthe first GMD 1704-1 to the first synchronized group 804-1. The GMD 1704may connect to a headset 120, which means a user may speak and hearthrough the headset 120 attached to the first GMD 1704-1 the appropriatevoice information transmitted in the mesh network 1700. Data that may betransferred through a GMD 1704 may include group identification numbersand/or a mesh network identification number. More than one mesh networkidentification number may be transferred.

The combined applicable information from the first synchronized group804-1 and the second synchronized group 804-2 is transferred through thesecond GMD 1704-2 via wired connections 228-3 and wired connection 228-4to a third synchronized group 804-3.

Information from a fourth synchronized group 804-4 is transferredthrough the third GMD 1704-3 via wired connections 228-6 and wiredconnection 228-5 to the third synchronized group 804-3. In a reversepath, the appropriate information from the first synchronized group804-1, the second synchronized group 804-2, and the third synchronizedgroup 804-3 is transferred through the third GMD 1704-3 via wiredconnections 228-6 and wired connection 228-5 to the fourth synchronizedgroup 804-4. Information from a sixth synchronized group 804-6 istransferred through a fifth GMD 1704-5 via wired connections 228-10 andwired connection 228-9 to a fifth synchronized group 804-5. Informationfrom a seventh synchronized group 804-7 is transferred through the a GMD1704-6 via wired connections 228-12 and wired connection 228-11 to thefifth synchronized group 804-5. The appropriate information from thefifth synchronized group 804-5, the sixth synchronized group 804-6, andthe seventh synchronized group 804-7 is transferred through the fourthGMD 1704-4 via wired connections 228-7 and wired connection 228-8 to thethird synchronized group 804-3. Thus information is shared between thesynchronized groups 804. A person talking on a multivoice radio 204 inthe first synchronized group 804-1 can communicate with any other personwith a multivoice radio 204 on any of the synchronized groups.

In one embodiment, an individual will have two multivoice radios 204with a GMD 1704 connecting the two multivoice radios 204. Eachmultivoice radio 204 on this individual will be part of a separatesynchronized group 804. In another embodiment, one or more long-rangeradios 220, or other type of radio, may be connected to the mesh network1700 as shown in previous embodiments and examples.

A mesh network, or a wireless conferencing system (e.g., a multivoiceradio system), may have a problem with too many open microphones. Thus,in an embodiment some radios have push-to-talk (PTT) capability. Invarious embodiments, a switch-to-talk (STT) capability is added; eitherin addition to PTT capability or without PTT capability. Unlike PTT,which is a momentary contact that has to be held down to activate amicrophone, a STT is a switch that when turned on activates a microphoneand transmission capability until the STT is turn to the off position.This STT can be put in line with the microphone or digitally activated.PTT and/or STT capabilities allow a number of radios connected togetherin a group to be very large. PTT and/or STT capabilities also allowradios to not take up a transmission slot as shown in the '115application. Radios with PTT and/or STT functionality can be listen-onlydevices until a switch or button is activated at which time the radiowill try to take up a transmission slot.

In some full-duplex radios, one frequency is used to transmit on and aseparate frequency is used to receive on. To keep a transmitter functionfrom interfering with a receiver function, the transmitter and thereceiver frequencies are separated enough to use filters to preventinterference. As the frequency separation between the transmitter andreceiver gets closer, the filter may get more expensive, or the systemmay use more power to help isolate and filter the transmitter from thereceive path. In one embodiment, to limit the transmitter function frominterfering with the receiver function, two independent transceivers,where possible, transmit at the same time and receive at the same time.One method to accomplish follows:

-   -   1. When a first transceiver turns on and is a master, the first        transceiver queries if other transceivers are within range.    -   2. If the first transceiver finds an appropriate second        transceiver within range, the first transceiver may use the        timing of when the first transceiver senses the second        transceiver starting to transmit to set the first transceiver's        timing so the first transceiver transmits at the same time as        the second transceiver. The first transceiver may then hop to a        different frequency and start a transmit protocol so that the        first transceiver transmits at the same time as the second        transceiver.    -   3. In cases where multiple appropriate transceivers are within        range of the first transceiver that just turns on, the first        transceiver may first looks for all appropriate transceivers        within range and adjusts the timing of the first transceiver to        a transceiver that is closest based on signal strength of        signals the first transceiver receives from the multiple        appropriate transceivers that are within range.    -   4. Transceivers may use another independent timing source, like        GPS timing. Or, transceivers may periodically sense a timing of        another transceiver the transceiver is synchronized to so that        adjustment in timing may occur to the multiple appropriate        transceivers.

When a second transceiver on a GRE 1504 turns on, the second transceivermay use the above protocol to synchronize to the first transceiver, butan appropriate transceiver the second transceiver may look for is athird transceiver, located on the same GRE 1504. Thus the secondtransceiver and third transceiver, both located on the GRE 1504, maytransmit at the same time.

When a mesh network system is using the above protocol, or somethingsimilar to it, the protocol may need to account for two transceiversthat do not control the timing of other transceivers that are right nextto each other. A transceiver that controls a timing of anothertransceiver is a master. A transceiver that has its timing controlled bya master is called a slave. Several transceivers that have the sametiming controlled by a specific master will be called a synchronizedgroup 804. In a mesh network, several groups may be in the same area.FIG. 17 shows a mesh network 1700 with several groups in the same areathough several groups may be out of range of other groups. As the meshnetwork 1700 is being formed, master transceivers may use the aboveprotocol for synchronizing in timing with other master transceivers whenappropriate. A possible example of the mesh network 1700 forming is asfollows:

-   -   1. Assume that multivoice radios 204 connected to the first GMD        1704-1 are master transceivers that use the above method to        synchronize. This means a first multivoice radio 204-1 that is a        master and that is connected to the first GMD 1704-1 is part of        the first synchronized group 804-1 and provides all the timing        for the first synchronized group 804-1. A second multivoice        radio 204-2 that is a master and that is connected to the first        GMD 1704-1 is part of the second synchronized group 804-2.    -   2. Assume a third multivoice radio 204-3 that is connect to the        second GMD 1704-2 and is part of the second synchronized group        804-2 is a slave. Since a fourth multivoice radio 204-4 that is        connected to the second GMD 1704-2 is right next to the third        multivoice radio 204, the fourth multivoice radio 204-4 may use        the timing of the third multivoice radio 204-3 transmitting so        that the fourth multivoice radio 204-4 and the third multivoice        radio 204-3 transmit at the same time. Thus when the fourth        multivoice radio 204 turns on, the fourth multivoice radio 204-4        may look for other multivoice radio 204 transceivers in the area        but it may see the third multivoice radio 204-3 as a slave and        being extremely close. The fourth multivoice radio 204-3 then        can use the third multivoice radio 204 transmission timing        instead of the second master multivoice radio 204-2 transmission        timing for synchronizing transmitting timing of the fourth        multivoice radio 204-4. The fourth multivoice radio 204-4 may        then periodically go back and sense the start of the third        multivoice radio 204-3 transmitting to adjust for timing error.    -   3. Assume a fifth multivoice radio 204-5 is a master and is        connected to the fourth synchronized group 804-4 and is        connected to the third GMD 1704-3; and assume the fourth        synchronized group 804-4 was formed before becoming part of the        mesh network 1700. Before joining the mesh network 1700 a sixth        multivoice radio 204-6 that is connected to the third GMD 1704-3        may be looking for other master transceivers to join and create        or add to a mesh network. When the sixth multivoice radio 204-6        senses a seventh multivoice radio 204-7 that is a master of the        third synchronized group 804-3 and requests to join the third        synchronized group 804-3, the sixth multivoice radio 204-6 may        need to adjust its timing so it will transmit at the same time        as the fifth multivoice radio 204-5. The sixth multivoice radio        204-6 may either ask a seventh multivoice radio 204-7, which is        a master, for an appropriate transmission timing to match the        fifth multivoice radio 204-5 transmission timing or the seventh        multivoice radio 204-7 may communicate to the fifth multivoice        radio 204-5 to synchronize to the timing of sixth multivoice        radio 204-5, which in turn may cause an adjustment of timing for        the fourth synchronized group 804-4, or a combination of        adjustment of timing for both the third synchronized group 804-3        and the fourth synchronized group 804-4 may be used, which may        cause an adjustment of timing for the whole mesh network 1700.    -   4. Assume a fifth multivoice radio 204-5, which is connected to        the fourth synchronized group 804-4 and is connected to the        third GMD 1704-3, is a slave and the fourth synchronized group        804-4 is not part of a mesh network 1700. Before joining the        mesh network 1700 the sixth multivoice radio 204-6 that is        connected to the third GMD 1704-3 may be looking for other        master transceivers to join and create or add to a mesh network.        When the sixth multivoice radio 204-6 senses the seventh        multivoice radio 204-7, which is master of the third        synchronized group 804-3, and requests to join the third        synchronized group 804-3, the sixth multivoice radio 204-6 may        need to adjust its timing so it will transmit at the same time        as the fifth multivoice radio 204-5. The sixth multivoice radio        204-6 may either ask the seventh multivoice radio 204-7 for an        appropriate transmission timing to match the fifth multivoice        radio 204-5 transmission timing, or the seventh multivoice radio        204-7 may cause timing on the sixth multivoice radio 204-6 to        change, which in turn may be sensed by the fifth multivoice        radio 205-5, which may change the fifth multivoice radio 205-5        timing as well which may be communicated to the master        multivoice radio of group 804-4 to change the timing of the        fourth synchronized group 804-4 or a combination of adjustment        of timing for both the third synchronized group 804-3 and the        fourth synchronized group 804-4. Timing changes to the third        synchronized group 804-3 may cause an adjustment of timing for        the whole mesh network 1700. The fifth multivoice radio 204-5        may request that the master multivoice radio 204 of the fourth        synchronized group 804-4 adjust its timing so that the fifth        multivoice radio 204-5 transmits at the same time as the sixth        multivoice radio 204-6. This may be done in several ways. One        way would be for the fifth multivoice radio 204-5 to request a        different slave transmission timing or time slot from the master        multivoice radio 204 of the fourth synchronized group 804-4. The        slave may just ask for the master to make timing adjustment        until the fifth multivoice radio 204-5 and the sixth multivoice        radio 204-6 are transmitting at the same time. The fifth        multivoice radio 204-5 may also ask to become the master of the        fourth synchronized group 804-4, after which the fifth        multivoice radio 204-5 can more easily adjust the timing of the        fourth synchronized group 804-4. When these kinds of changes        occur in a system, timing changes may cause timing changes to        ripple through the whole mesh network 1700 so appropriate        transceivers are transmitting at the same time.

In FIG. 18, a flowchart of an embodiment of a process for configuring aradio between a transmit mode and a listen-only mode is illustrated. Asexplained in FIG. 15, a multivoice system uses time-divisionmultiplexing and a given time period is divided into a plurality oftransmission slots. When a multivoice radio 204 receives a transmissionslot assignment, the multivoice radio 204 is said to be in a transmitmode. A problem arises when there are more multivoice radios 204 thanavailable transmission slots. In some embodiments, a multivoice radio204 is configured to only receive transmissions. When a multivoice radio204 is configured to only receive transmissions, the multivoice radio204 is in a listen-only mode. By having some multivoice radios 204 inthe listen-only mode, more multivoice radios 204 can be added to amultivoice radio system than there are transmission slots available.

In some embodiments, a switch-to-talk (STT) button (or switch, toggle,rocker, etc.), is added to a multivoice radio 204 to toggle themultivoice radio 204 between the transmit mode and the listen-only mode.A STT method 1800 is a method for changing a multivoice radio 204between the transmit mode and the listen-only mode. The method 1800begins in step 1804 where the multivoice radio determines whether theSTT button is activated. If the STT button is activated, then theprocess flows to step 1820. If the STT button is not active (such asturned off), the process flows to step 1808.

In step 1808, the multivoice radio 204 determines whether the multivoiceradio is already in the listen-only mode. If the multivoice radio 204 isalready in the listen-only mode, then there is no change 1812. If themultivoice radio 204 is not in the listen-only mode, then the multivoiceradio 204 switches to the listen-only mode 1816. When a multivoice radio204 is in the listen-only mode, the multivoice radio 204 no longer takesa transmission slot.

In step 1820 the multivoice radio 204 determines if the multivoice radio204 has a push-to-talk (PTT) button. If the multivoice radio 204 has aPTT button, then the process flows to step 1824 and the multivoice radio204 determines if the PTT button is pushed. If the PTT button is notpushed then the process flows to step 1808. If it is determined that thePTT button is pushed or if the multivoice radio 204 is not a PTT radio,the process flows to step 1828. In step 1828, the multivoice radio 204determines whether the multivoice radio 204 is already in transmit mode.If the multivoice radio 204 is already in transmit mode, i.e., assigneda transmission slot, then there is no change 1812. If the multivoiceradio 204 is not in the transmit mode, then the multivoice radio 204switches to the transmit mode. The multivoice radio 204 can switch tothe transmit mode by requesting a transmission slot from a master.

There are also several other embodiments of using STT. In onealternative embodiment, the STT switch is located remotely from themultivoice radio 204. A remote STT switch could be wired or wireless.For example the STT switch could be located on a headset. In anotherexample, the STT switch is placed on an assault rifle and communicateswirelessly with the multivoice radio 204. Further, STT can also be usedfor radio discipline, for example so that not so many users are heard atthe same time. In other embodiments, a multivoice radio 204 acting as amaster can perform one or more steps of the STT method 1800. In otherembodiments an external unit can be added to the multivoice radio 204,such as a signal compounder 104 or a specially made unit can perform oneor more of the steps in the STT method 1800. In still furtherembodiments, there does not need to be a manually operated STT switch.For example, a multivoice radio 204 could switch to the transmit modebased on a volume threshold from the microphone being reached. And amultivoice radio could switch to the listen-only mode if a second volumethreshold from the microphone is not reached in a given time period. Forexample, if a user does not speak into a microphone of the multivoiceradio 204 for sixty seconds, then the multivoice radio 204 could switchfrom the transmit mode to the listen-only mode. In another example, oneor more transmission slots are reserved for emergencies. A multivoiceradio 204 that is assigned an emergency transmission slot isautomatically removed by the master from the emergency transmit slotafter ten or fifteen seconds. A signal on a management transmission slotcould be used, or even a signal of a different frequency could be usedto relay the STT button selection. A management transmission slot is atransmission slot reserved for transferring data, other than voice.Additionally, there could also be a hierarchy of STT buttons. Forexample, if a user had a remote STT button and a STT on the multivoiceradio 204 and the remote STT button was selecting the transmit mode butthe STT button on the multivoice radio 204 selecting the listen-onlymode, the remote STT button could control and the multivoice radio 204would switch to the transmit mode. In another embodiment, a multivoiceradio 204 can request that all low priority radios be set to listen-onlymode either through a normal transmission time slot or through themanagement transmission slot. Or a multivoice radio 204 may requestindividual multivoice radios 204 go to listen-only mode either throughthe normal transmission time slot or through the management transmissionslot.

Different arrangements of the components depicted in the drawings ordescribed above, as well as components and steps not shown or describedare possible. Similarly, some features and subcombinations are usefuland may be employed without reference to other features andsubcombinations. Embodiments of the invention have been described forillustrative and not restrictive purposes, and alternative embodimentswill become apparent to readers of this patent. Accordingly, the presentinvention is not limited to the embodiments described above or depictedin the drawings, and various embodiments and modifications can be madewithout departing from the scope of the claims below.

The subject matter of embodiments of the present invention is describedhere with specificity to meet statutory requirements, but thisdescription is not necessarily intended to limit the scope of anyclaims. The object matter may be embodied in other ways, may includedifferent elements or steps, and may be used in conjunction with otherexisting or future technologies. This description should not beinterpreted as implying any particular order or arrangement among orbetween various steps or elements except when the order of individualsteps or arrangement of elements is explicitly described.

Though some figures show radios that look like hand-held radios and thisdisclosure often describes using radios, embodiments of the inventioncan apply to non-hand-held radios including stationary radios located ina building or vehicle, mobile phones, and/or to telephones. One side ofthe communication system will be a single user full-duplex type radiothat is usually meant for one person like a cell phone. This single userradios can be connected together into a conferencing system like cellphones are currently combined into a conference call through the use ofa base station. Further, though this application uses the phrase “radiocommunication,” the term “radio” in not meant to limit communication toradio frequencies. Instead “radio,” when referring to radiocommunication, refers to communication using a frequency or plurality offrequencies in the electro-magnetic spectrum.

A number of variations and modifications of the disclosed embodimentscan also be used. For example, many embodiments refer to the firsttransceiver 108 as a short-range transceiver and the second transceiver110 as a long-range transceiver. But other embodiments could have thefirst transceiver 108 as a long-range transceiver and the secondtransceiver 110 as a short-range transceiver. Further, the firsttransceiver 108 and the second transceiver 110 could have roughly, orexactly, the same range. Additionally, many embodiments showed thesignal compounder 104 in communication with the PTT long-range radio220. In other embodiments, other types of radios can be substituted forthe PTT long-range radio 220. For example, a duplex radio, such as acell phone could replace the long-range radio 220.

Specific details are given in the above description to provide athorough understanding of the embodiments. However, it is understoodthat the embodiments may be practiced without these specific details.For example, circuits may be shown in block diagrams in order not toobscure the embodiments in unnecessary detail. In other instances,well-known circuits, processes, algorithms, structures, and techniquesmay be shown without unnecessary detail in order to avoid obscuring theembodiments.

Implementation of the techniques, blocks, steps and means describedabove may be done in various ways. For example, these techniques,blocks, steps and means may be implemented in hardware, software, or acombination thereof. For a hardware implementation, the processing unitsmay be implemented within one or more application specific integratedcircuits (ASICs), digital signal compounders (DSPs), digital signalprocessing devices (DSPDs), programmable logic devices (PLDs), fieldprogrammable gate arrays (FPGAs), processors, controllers,micro-controllers, microprocessors, other electronic units designed toperform the functions described above, and/or a combination thereof.

Also, it is noted that the embodiments may be described as a processwhich is depicted as a flowchart, a flow diagram, a swim diagram, a dataflow diagram, a structure diagram, or a block diagram. Although adepiction may describe the operations as a sequential process, many ofthe operations can be performed in parallel or concurrently. Inaddition, the order of the operations may be re-arranged. A process isterminated when its operations are completed, but could have additionalsteps not included in the figure. A process may correspond to a method,a function, a procedure, a subroutine, a subprogram, etc. When a processcorresponds to a function, its termination corresponds to a return ofthe function to the calling function or the main function.

Furthermore, embodiments may be implemented by hardware, software,scripting languages, firmware, middleware, microcode, hardwaredescription languages, and/or any combination thereof. When implementedin software, firmware, middleware, scripting language, and/or microcode,the program code or code segments to perform the necessary tasks may bestored in a machine readable medium such as a storage medium. A codesegment or machine-executable instruction may represent a procedure, afunction, a subprogram, a program, a routine, a subroutine, a module, asoftware package, a script, a class, or any combination of instructions,data structures, and/or program statements. A code segment may becoupled to another code segment or a hardware circuit by passing and/orreceiving information, data, arguments, parameters, and/or memorycontents. Information, arguments, parameters, data, etc. may be passed,forwarded, or transmitted via any suitable means including memorysharing, message passing, token passing, network transmission, etc.

For a firmware and/or software implementation, the methodologies may beimplemented with modules (e.g., procedures, functions, and so on) thatperform the functions described herein. Any machine-readable mediumtangibly embodying instructions may be used in implementing themethodologies described herein. For example, software codes may bestored in a memory. Memory may be implemented within the processor orexternal to the processor. As used herein the term “memory” refers toany type of long term, short term, volatile, nonvolatile, or otherstorage medium and is not to be limited to any particular type of memoryor number of memories, or type of media upon which memory is stored.

Moreover, as disclosed herein, the term “storage medium” may representone or more memories for storing data, including read only memory (ROM),random access memory (RAM), magnetic RAM, core memory, magnetic diskstorage mediums, optical storage mediums, flash memory devices and/orother machine readable mediums for storing information. The term“machine-readable medium” includes, but is not limited to portable orfixed storage devices, optical storage devices, and/or various otherstorage mediums capable of storing that contain or carry instruction(s)and/or data.

While the principles of the disclosure have been described above inconnection with specific apparatuses and methods, it is to be clearlyunderstood that this description is made only by way of example and notas limitation on the scope of the disclosure.

What is claimed is:
 1. A wireless-conferencing radio system implementingtime division multiple access (TDMA), the wireless-conferencing radiosystem comprising: a master radio configured to: assign the master radioto a first transmission slot of a plurality of transmission slots, fortransmitting audio communication during the first transmission slot,wherein the plurality of transmission slots are subdivisions of asegment of time; assign a first slave radio to a second transmissionslot of the plurality of transmission slots, for transmitting audiocommunication during the second transmission slot; and assign, inresponse to a second slave radio operating in a transmit mode, thesecond slave radio to a third transmission slot of the plurality oftransmission slots, for transmitting audio communication during thethird transmission slot; the first slave radio configured to receive anassignment from the master radio to transmit during the secondtransmission slot; and the second slave radio configured to: operate ina listen mode, wherein operating in the listen mode comprises the secondslave radio being configured to: receive wireless communication from themaster radio during the first transmission slot; receive wirelesscommunication from the first slave radio during the second transmissionslot; and not receiving an assignment to transmit audio communication onany transmission slot of the plurality of transmission slots; andoperate in the transmit mode, wherein operating in the transmit modecomprises the second slave radio being configured to: receive wirelesscommunication from the master radio during the first transmission slot;receive wireless communication from the first slave radio during thesecond transmission slot; and receive an assignment from the masterradio to transmit audio communication during the third transmission slotof the plurality of transmission slots.
 2. The wireless-conferencingradio system as recited in claim 1, wherein the second slave radioswitches between operating in the listen mode and operating in thetransmit mode based on an activation of a switch on the second slaveradio.
 3. The wireless-conferencing radio system as recited in claim 2,wherein the second slave radio is further configured to: limit thesecond slave radio from transmitting audio communication when apush-to-talk button on the second slave radio is not activated, whereinthe push-to-talk button is different from the switch; and allow thesecond slave radio to transmit audio communication during the thirdtransmission slot when the push-to-talk button is activated.
 4. Thewireless-conferencing radio system as recited in claim 1, wherein whenthe second slave radio operates in the transmit mode, the second slaveradio is configured to transmit audio communication to the master radioand to the first slave radio during the third transmission slot.
 5. Thewireless-conferencing radio system as recited in claim 1, wherein: thefirst slave radio is further configured to receive the assignment fromthe master radio to transmit during the second transmission slot after aswitch to the first slave radio is activated, and previous to activationof the switch to the first slave radio, the first slave radio was in asecond listen mode comprising the first slave radio being configured to:receive wireless communication from the master radio during the firsttransmission slot; and not receive an assignment to transmit audiocommunication on any transmission slot of the plurality of transmissionslots.
 6. The wireless-conferencing radio system as recited in claim 1,wherein the master radio, the first slave radio, and the second slaveradio implement at least one protocol selected from the group consistingof: frequency hopping, spread spectrum, direct sequence spread spectrum,ultra wideband, frequency division multiple access, packet mode multipleaccess, and space division multiple access.
 7. A method for operating afirst radio, the method comprising: operating the first radio in a firstmode, wherein operating the first radio in the first mode comprises:operating the first radio in a time-division multiplexed radio system;receiving wireless communication from a second radio during a firsttransmission slot of a plurality of transmission slots, wherein asegment of time is subdivided into the plurality of transmission slots;receiving wireless communication from a third radio during a secondtransmission slot of the plurality of transmission slots; and the firstradio not being assigned to a transmission slot of the plurality oftransmission slots, wherein the first radio does not transmit audiocommunication; operating the first radio in a second mode, whereinoperating the first radio in the second mode comprises: operating thefirst radio in the time-division multiplexed radio system; receivingwireless communication from the second radio during the firsttransmission slot, receiving wireless communication from the third radioduring the second transmission slot, and the first radio being assignedto a third transmission slot of the plurality of transmission slots; andreceiving an indication to switch from operating in the first mode tooperating in the second mode, or from operating in the second mode tooperating in the first mode.
 8. The method as recited in claim 7,wherein the indication is received via a switch on the first radio. 9.The method as recited in claim 7, wherein the first radio is assigned tothe third transmission slot by the second radio.
 10. The method asrecited in claim 7, wherein the indication is received from the secondradio and the first radio switches from operating in the second mode tooperating in the first mode.
 11. The method as recited in claim 7,wherein the first radio operating in the second mode comprisestransmitting audio communication to the first radio and to the secondradio during the third transmission slot.
 12. The method as recited inclaim 7, wherein the first radio operating in the first mode comprisestransmitting non-audio data to the second radio.
 13. The method asrecited in claim 7, wherein the indication is a microphone being pluggedor unplugged from the first radio.
 14. A radio comprising: a receiver,wherein: the receiver is configured to receive wireless communicationfrom a second radio and a third radio, the second radio transmits duringa first transmission slot of a plurality of transmission slots, thethird radio transmits during a second transmission slot of the pluralityof transmission slots, and the plurality of transmission slots aresubdivisions of a segment of time; a transmitter for transmittingwireless communication; and circuitry configured to operate the radio inat least two modes comprising a first mode and a second mode, wherein:the radio operating in the first mode is not assigned to a transmissionslot of the plurality of transmission slots for transmitting audiocommunication, and the radio operating in the second mode is assigned toa third transmission slot of the plurality of transmission slots fortransmitting audio communication.
 15. The radio as recited in claim 14,the radio further comprising a manual switch that, when activated,switches the radio from operating in the first mode to operating in thesecond mode, or from operating in the second mode to operating in thefirst mode.
 16. The radio as recited in 15, the radio further comprisinga push-to-talk button.
 17. The radio as recited in claim 14, wherein theradio, when operating in the second mode, transmits audio communicationto the second radio and to the third radio during the third transmissionslot.
 18. The radio as recited in claim 14, wherein the radio, whereinthe circuitry comprises a digital processor.
 19. The radio as recited inclaim 14, the radio further comprising a connection to a microphone,wherein in response to the microphone being unplugged from the radio orturned off, the radio is switched from operating in the second mode tooperating in the first mode.
 20. The radio as recited in as recited inclaim 14, wherein the radio implements at least one protocol selectedfrom the group consisting of: frequency hopping, spread spectrum, directsequence spread spectrum, ultra wideband, frequency division multipleaccess, packet mode multiple access, and space division multiple access.